Serum inhibin B and anti-Müllerian hormone are not superior to follicle-stimulating hormone as predictors of the presence of sperm in testicular fine-needle aspiration in men with azoospermia

Role of Follicle-stimulating Hormone, Inhibin B, and Anti-Müllerian Hormone in Predicting Sperm Retrieval from Men with Nonobstructive Azoospermia Undergoing Microdissection Testicular Sperm Extraction: A Systematic Review and Meta-analysis

Background and objective

No clear-cut markers for predicting positive sperm retrieval (+SR) at microdissection testicular sperm extraction (mTESE) have been identified thus far. Our aim was to conduct a systematic review and meta-analysis to evaluate the ability of follicle-stimulating hormone (FSH), inhibin B (InhB), and anti-Müllerian hormone (AMH) to predict +SR in men with nonobstructive azoospermia (NOA) undergoing mTESE.

Methods

We performed a search in the PubMed, EMBASE, Web of Science, and Scopus databases according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement. Thirty-four publications were selected for inclusion in the analysis.

Key findings and limitations

Overall, the mean +SR rate was 45%. Pooled standardized mean difference (SMD) values revealed significant hormonal differences between the +SR and -SR groups, with lower FSH (SMD -0.30), higher InhB (SMD 0.54), and lower AMH (SMD -0.56) levels in the +SR group. Pooled odds ratios (Ors) revealed no significant prediction of +SR by either FSH (OR 1.03, 95% confidence interval [CI] 1.00-1.06) or InhB (OR 1.01, 95% CI 1.00-1.02), despite variations in baseline levels and study heterogeneity. Conversely, AMH had significant predictive value (OR 0.82, 95% CI 0.73-0.92), with lower baseline levels in the +SR group. InhB and FSH levels were higher in the +SR group, while InhB exhibited the opposite trend.

Conclusions and clinical implications

Despite study heterogeneity, our meta-analysis findings support the ability of AMH to predict +SR for men with NOA undergoing mTESE.

Patient summary

We conducted a review and analysis of results from previous studies. Our findings show that for men with an infertility condition called nonobstructive azoospermia, blood levels of anti-Müllerian hormone can predict successful extraction of sperm using a microsurgical technique. Levels of two other hormones did not predict successful sperm extraction.

Evaluating testicular function changes in unilateral cryptorchid chinese infants underwent orchidopexy in the first year of life

OBJECTIVE

Management of cryptorchidism is typically recommended within the first 18 months of life to maximize fertility potential. However, there is a paucity of longitudinal postoperative data for Chinese infants. We aim to evaluate the Testicular function change when the procedure is done within the first year of life.

METHOD

We prospectively enrolled 51 children diagnosed with unilateral inguinal cryptorchidism into the surgical group between January 2021 and January 2022. Orchidopexy was carried out through a single transverse scrotal incision. Assessments of anti-Mullerian hormone (AMH), inhibin B (InhB), testosterone (T) levels, testicular volume and testicular atrophy index (TAI) were conducted at baseline, 6 months, and 1 year following surgery. Concurrently, clinical data from 42 healthy age-matched controls were collected during their routine physical examinations.

RESULTS

At 6- and 12-months post-surgery, testicular volume increased significantly to 0.98 ± 0.12 mL and 1.01 ± 0.12ml. AMH levels also rose from 76.40 ± 15.77 ng/mL to 81.52 ± 15.32 ng/mL and 87.50 ± 15.36 ng/mL. However, these parameters are significantly lower than age-matched healthy controls (both P < 0.001). InhB levels significantly increased after surgery and even surpassed those of healthy controls after 6 months (both P < 0.001). The TAI was 16.7% and 8.6% at 6- and 12-months following surgery.

CONCLUSION

Although orchiopexy can improve testicular growth and function, the restoration of testicular function to the level of healthy peers might take longer. To expedite the recovery of testicular function and bring it in line with that of peers, we recommend addressing cryptorchidism at the earliest opportunity.

A Prediction Model of Sperm Retrieval in Males with Idiopathic Non-obstructive Azoospermia for Microdissection Testicular Sperm Extraction

Patients with Idiopathic non-obstructive azoospermia (iNOA) can achieve fertility by extracting testicular sperm through microdissection testicular sperm extraction (mTESE). But more than half of iNOA patients still cannot benefit from mTESE. In recent years, some studies had reported that serum hormones may be related to the outcome of sperm retrieval, but few had been verified. We hope to obtain a predictive method that is convenient for clinical application and can help judge the outcome of sperm extraction before implementing mTESE. We performed a retrospective analysis of NOA patients who underwent mTESE in the same andrology center from June 2020 to November 2022. A total of 261 patients with complete data were collected, logistic regression analysis was performed and a predictive model was constructed. Then, from December 2022 to May 2023, one prospective cohort of 48 NOA patients who met the inclusion criteria from the same center was recruited to validate the risk prediction model. We successfully constructed a logistic regression model to predict the outcome of iNOA patients undergoing mTESE and found that higher serum anti-Müllerian hormone (AMH) levels were associated with failure sperm retrieval, resulting in an AMH cut-off of 2.60 ng/ml. The area under the receiver operating curve was 0.811, the sensitivity was 0.870, and the specificity was 0.705. Decision curve analysis demonstrated that the threshold probability was above 4%, and unnecessary mTESE could be reduced using this model. In a prospective cohort at the same center, 85.42% (41/48) of iNOA patients correctly identified the mTESE outcome using this model. A logistic regression model with AMH as an independent predictor can predict mTESE outcomes in iNOA patients. Preoperative selection of mTESE in patients with iNOA using this model had clinical benefit in reducing unnecessary surgery. The model demonstrated good accuracy in a small prospective cohort validation.

Noninvasive Prediction of Sperm Retrieval Using Diffusion Tensor Imaging in Patients with Nonobstructive Azoospermia

Microdissection testicular sperm extraction (mTESE) is the first-line treatment plan for nonobstructive azoospermia (NOA). However, studies reported that the overall sperm retrieval rate (SRR) was 43% to 63% among men with NOA, implying that nearly half of the patients fail sperm retrieval. This study aimed to evaluate the diagnostic performance of parameters derived from diffusion tensor imaging (DTI) in predicting SRR in patients with NOA. Seventy patients diagnosed with NOA were enrolled and classified into two groups based on the outcome of sperm retrieval during mTESE: success (29 patients) and failure (41 patients). Scrotal magnetic resonance imaging was performed, and the DTI parameters, including mean diffusivity and fractional anisotropy, were analyzed between groups. The results showed that there was a significant difference in mean diffusivity values between the two groups, and the area under the curve for mean diffusivity was calculated as 0.865, with a sensitivity of 72.2% and a specificity of 97.5%. No statistically significant difference was observed in fractional anisotropy values and sex hormone levels between the two groups. This study demonstrated that the mean diffusivity value might serve as a useful noninvasive imaging marker for predicting the SRR of NOA patients undergoing mTESE.

Anti-Müllerian hormone predicts positive sperm retrieval in men with idiopathic non-obstructive azoospermia-findings from a multi-centric cross-sectional study

STUDY QUESTION

Is it possible to identify a reliable marker of successful sperm retrieval (+SR) in men with idiopathic non-obstructive azoospermia (iNOA) undergoing microdissection testicular sperm extraction (mTESE)?

SUMMARY ANSWER

A higher likelihood of +SR during mTESE is observed in men with iNOA and lower preoperative serum anti-Müllerian hormone (AMH) levels, with good predictive accuracy achieved using an AMH threshold of <4 ng/ml.

WHAT IS KNOWN ALREADY

AMH has been previously linked to +SR in men with iNOA undergoing mTESE prior to ART.

STUDY DESIGN, SIZE, DURATION

A multi-centre cross-sectional study was carried out with a cohort of 117 men with iNOA undergoing mTESE at three tertiary-referral centres.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data from 117 consecutive white-European men with iNOA presenting for primary couple's infertility associated with a pure male factor at three centres were analysed. Descriptive statistics was applied to compare patients with negative (-SR) versus +SR at mTESE. Multivariate logistic regression models were fitted to predict +SR at mTESE, after adjusting for possible confounders. Diagnostic accuracy of the factors associated with +SR was assessed. Decision curve analyses were used to display the clinical benefit.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, 60 (51.3%) men had an -SR and 57 (48.7%) had a +SR at mTESE. Patients with +SR had lower levels of baseline AMH (P = 0.005) and higher levels of estradiol (E2) (P = 0.01). At multivariate logistic regression analysis, lower levels of AMH (odds ratio: 0.79; 95% CI: 0.64-0.93, P = 0.03) were associated with +SR at mTESE, after adjusting for possible confounders (e.g. age, mean testicular volume, FSH, and E2). A threshold of AMH <4 ng/ml achieved the highest accuracy for +SR at mTESE, with an AUC of 70.3% (95% CI: 59.8-80.7). Decision curve analysis displayed the net clinical benefit of using an AMH <4 ng/ml threshold.

LIMITATIONS, REASONS FOR CAUTION

There is a need for external validation in even larger cohorts, across different centres and ethnicities. Systematic reviews and meta-analysis to provide high level of evidence are lacking in the context of AMH and SR rates in men with iNOA.

WIDER IMPLICATIONS OF THE FINDINGS

Current findings suggest that slightly more than one in two men with iNOA had -SR at mTESE. Overall, men with iNOA with lower levels of AMH had a significantly higher percentage of successful SR at surgery. A threshold of <4 ng/ml for circulating AMH ensured satisfactory sensitivity, specificity, and positive predictive values in the context of +SR at mTESE.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by voluntary donations from the Urological Research Institute (URI). All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

An update on male infertility and intratesticular testosterone-insight into novel serum biomarkers

Intratesticular testosterone is vital for spermatogenesis, male fertility, and virility. Currently the only method to assess levels of intratesticular testosterone is to perform testicular biopsy which is invasive and can lead to several complications. Approaches to assess intratesticular testosterone have been understudied but hold promise as future male contraceptive agents and may grant the ability to monitor patients undergoing hormonal changes from therapeutic and diagnostic perspectives. Previous studies have sought to assess the utility of 17-hydroxyprogesterone (17-OHP) and insulin-like factor 3 (INSL3) as accurate surrogate biomarkers of intratesticular testosterone. The aim of this review is thus to highlight the importance of intratesticular testosterone and the consequent advances that have been made to elucidate the potential of biomarkers for intratesticular testosterone in the context of male infertility.

A novel mutation of AMHR2 in two brothers with persistent Müllerian duct syndrome and their intracytoplasmic sperm injection outcome

Background

Persistent Müllerian duct syndrome (PMDS) is defined as the presence of Müllerian duct derivatives in an otherwise normally virilized 46, XY male. It is usually caused by homozygous or compound heterozygous mutations in either the anti‐Müllerian hormone (AMH) or AMH receptor type 2 (AMHR2) genes. The main purpose of the study is to determine the novel mutations of AMHR2 in PMDS patients and their intracytoplasmic sperm injection outcomes (ICSI).

Methods

Whole‐exome sequencing (WES) was carried out. Sanger sequencing was used to detect mutations in AMHR2. The pathogenicity of the identified variant and its possible effects on the protein were evaluated with in silico tools. The expression level of AMHR2 was determined by Western blotting. The spermatogenic function was evaluated by testicular sperm aspiration and histopathologic examination. The ICSI outcomes were recorded.

Results

We present two brothers with a history of bilateral cryptorchidism with orchidopexy and infertility due to azoospermia. A novel compound heterozygous mutation of c.1219C>T [p.R407X] and c.1387C>T [p.R463C] in exons 9 and 10 of AMHR2 (NM_020547.2) was detected by whole‐exome sequencing (WES). Spermatozoon could be retrieved from the two patients by testicular aspiration following intracytoplasmic sperm injection (ICSI) due to azoospermia. Finally, patient 1 had two healthy boys and patient 2 failed to conceive after three ICSI attempts.

Conclusion

The spermatozoa could obtain from PMDS patients due to azoospermia. For patients with bilateral cryptorchidism, PMDS should be included in the differential diagnosis and that genetic counseling needs to be considered when they seek reproductive help.

Anti-Müllerian hormone level as a predictor of sperm retrieval with microdissection testicular sperm extraction in nonobstructive azoospermia

Limited factors effectively predict sperm retrieval with microdissection testicular sperm extraction in men with nonobstructive azoospermia. We therefore sought to evaluate the role of serum anti-Müllerian hormone as a predictive biomarker for successful sperm retrieval. We included patients with pre-operative anti-Müllerian hormone levels and stratified them based on prior history of prior sperm retrieval procedure. We compared hormone levels between those who did and did not have a successful sperm retrieval and used receiver operating curves to determine an optimal cut-off value. A total of 46 men were included, of whom 18 (39.1%) had no prior sperm retrieval and 11 (61.1%) had sperm successfully retrieved. Pre-operative serum anti-Müllerian hormone levels were predictive of sperm retrieval in patients with no prior attempts at retrieval (p = .03). Receiver operating curve for those without prior retrieval was 0.6753. The optimal anti-Müllerian hormone cut-off for those without prior sperm retrieval was 0.133 ng/ml with a sensitivity of 0.91 and specificity of 0.29. Therefore, serum anti-Müllerian hormone levels have modest predictive value for sperm retrieval in this cohort. The combination of clinical history, examination and laboratory investigations should continue to be used to guide surgeons in counselling patients regarding the chance of sperm retrieval.

Hormonal markers as noninvasive predictors of sperm retrieval in non-obstructive azoospermia

Non-obstructive azoospermia (NOA) is one of the leading causes of male factor infertility, which results from impaired spermatogenesis. Currently, the sole feasible therapeutic option for men with NOA to father their biologic children is sperm retrieval by testicular sperm extraction (TESE) approaches followed by an intracytoplasmic sperm injection program. Nevertheless, the rate of sperm retrieval from NOA men following TESE has remained as low as 50%, leading to a significant number of unsuccessful TESE operations. Given that TESE is associated with multiple side effects, the prediction of TESE outcome preoperatively can abolish unnecessary operations and thereby prevent NOA patients from sustaining adverse side effects. As the process of spermatogenesis is under the regulation of hormones, the hormonal profile of serum and/or seminal plasma may contain useful information about spermatogenesis status and can potentially predict the chance of sperm retrieval from NOA patients. A large body of literature is available on the predictive capability of different serum and seminal plasma hormones such as FSH, LH, testosterone, inhibin B, AMH, estradiol, prolactin, and leptin in a stand-alone basis or combinational fashion with respect to the TESE outcome. The present review aimed to evaluate the potential of these hormonal markers as noninvasive predictors of sperm retrieval in men with NOA.

25-Hydroxy cholecalciferol, anti-Müllerian hormone, and thyroid profiles among infertile men

BACKGROUND AND AIM

We examined the relationship among vit.D₃, AMH, FT3, FT4, and TSH, in addition to the serum levels of reproductive hormones (FSH, LH, prolactin, and free testosterone), in oligoasthenoteratozoospermia and azoospermia patients in a cohort of infertile men from Egypt to establish a clinical marker/cause-effect relationship.

METHODS

This cross-sectional cohort study was carried out on 301 men (105 males with oligoasthenoteratozoospermia and 96 males with azoospermia), in addition to 100 controls. Measurements of serum vit.D₃, AMH, FT3, FT4, and TSH levels, in addition to reproductive hormone assays, were performed on all included subjects, using ELISA kits.

RESULTS

Overall, results showed significantly lower serum levels of vit.D₃ in infertile men than in the controls, with a greater decrease observed in men with azoospermia than in oligoasthenoteratozoospermia patients, (p < .05 for all). Significantly higher serum TSH and FSH levels and significantly lower serum free testosterone levels were observed in males with azoospermia than in males with oligoasthenoteratozoospermia and the controls (p < .05 for both). There were no significant differences between the studied groups in terms of AMH, FT3 or FT4 levels. LH levels were negatively correlated with TSH levels and positively correlated with AMH levels among men with oligoasthenoteratozoospermia, while among men with azoospermia, LH levels were positively correlated with vit.D₃ levels (p < .05 for all).

CONCLUSION

Decreased Vit.D₃ could play a role in male infertility, in addition to abnormal thyroid function, which needs further investigation.

Fertility outcome after Intracytoplasmic Sperm Injection with surgically retrieved sperm

BACKGROUND

Surgically retrieved sperm samples and Intra Cytoplasmic Sperm Injection are indicated when we face severe sperm abnormalities such as azoospermia. The objective of this study was to assess the rates of clinical pregnancies and live births with sperm from testicular biopsies.

DESIGN

This was a retrospective descriptive study of all Intra Cytoplasmic Sperm Injection (ICSI) cycles performed with surgically retrieved sperm at the Nîmes University Hospital from January 1st, 2015 to December 31st, 2018. The main outcome was the clinical pregnancy rate. The secondary outcomes were the fertilization rate, the implantation rate and the live birth rate.

RESULTS

In all, 99 couples were treated at our center during this period and 164 ICSI cycles using surgically-collected sperm were performed. The men were 34.7 ± 7.4 years old on average at the time of undergoing testicular biopsy and the women were 32.15 ± 5.07 years at the time of ICSI. Out of 127 fresh embryo transfers, we observed 47 clinical pregnancies (37 %) and 45 live births (35.4 %). The average fertilization rate was 45 % and the implantation rate was 23.7 %. Among these infertile couples, 53 % obtained at least one clinical pregnancy and 42 % at least one live birth.

CONCLUSION

Testicular sperm extraction combined with ICSI is indicated in cases of male infertility linked with azoospermia or severe semen alteration. This technique offers couples a marvelous opportunity to have children with their own gametes.

Seminal Plasma Anti-Müllerian Hormone: A Potential AI-Boar Fertility Biomarker?

The anti-Müllerian hormone (AMH), a Sertoli cell-secreted glycoprotein that is present in seminal plasma (SP), is considered as a marker of spermatogenesis in humans. This study aimed to evaluate the presence of this hormone in boar SP, together with its putative relationship with sperm quality, function, and in vivo fertility parameters in liquid-stored semen samples. The concentration of SP-AMH was assessed in 126 ejaculates from artificial insemination (AI)-boars (n = 92) while using a commercial Enzyme-Linked ImmunoSorbent Assay (ELISA) kit with monoclonal antibodies specific for Sus scrofa AMH (CEA228Po, Cloud-clone). Sperm quality (concentration, motility, viability, and acrosome damage) and functionality (membrane lipid disorder and intracellular H₂O₂ generation) were assessed in semen samples at 0 and 72 h of liquid-storage. In addition, fertility parameters from 3113 sows inseminated with the AI-boars were recorded in terms of farrowing rate, litter size, number of stillbirths per litter, and the duration of pregnancy over a 12-month period. The results revealed that the SP-AMH concentration varied widely among boar ejaculates, with no differences among breeds. Moreover, the SP-AMH concentration proved to be a good predictive biomarker for sperm concentration (p ˂ 0.05), but poor for other sperm quality, functionality, and in vivo fertility parameters of liquid-stored semen samples from AI-boars.

Comparing the role of anti-Müllerian hormone as a marker of FSH action in male and female fertility

INTRODUCTION

Originally limited to the assessment of disorders of sex development, anti-Müllerian hormone (AMH) measurement has more recently been extended to several conditions affecting the reproductive axis in males and females. Follicle-stimulating hormone (FSH) regulation of gonadal function has been extensively studied, but its role on AMH production has been explored only recently.

AREAS COVERED

We addressed the relationship between FSH action on the gonads and the usefulness of AMH as a marker in conditions affecting the reproductive axis.

EXPERT OPINION

Sertoli cells are the most active cell population in the prepubertal testis. Serum AMH is an excellent marker of FSH action on Sertoli cell proliferation and function in patients with hypogonadotropic hypogonadism. Low serum AMH is expected to predict low sperm production and prompts initial FSH treatment followed by human chorionic gonadotropin (hCG) or luteinizing hormone (LH) addition. Gonadotropin treatment may be more effective if installed to mimic the postnatal activation stage of the hypothalamic-pituitary-testicular axis. In females, AMH secretion by small antral follicles is stimulated by FSH. Elevated AMH indicates increased follicle numbers and should be considered as a potential contraindication of gonadotropin treatment in infertile patients due to an increased risk of developing ovarian hyperstimulation syndrome.

Predictive significance of serum inhibin B on testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men

The purpose of this study was to determine the diagnostic accuracy of serum inhibin B (INHB) as a predictor of the retrieval outcome of testicular haploid gametes (spermatids and testicular spermatozoa) in nonobstructive azoospermic men. Serum hormone levels, testicular volume, and histological evaluation were performed in 403 Chinese nonobstructive azoospermic men. Testicular haploid gamete was successfully retrieved in 213 of 403 patients (52.85%). The haploid gamete group always had higher INHB levels than the non-haploid gamete group. According to the receiver operating characteristic (ROC) curve analysis, INHB was a good predictor of testicular haploid gamete retrieval outcome in all patients (sensitivity: 77.93% and specificity: 91.58%) and patients with normal follicle-stimulating hormone (FSH; sensitivity: 88.52% and specificity: 70.83%). The area under the ROC curve (AUC) of INHB was similar to that of FSH in all patients or patients with normal FSH. In patients with elevated FSH, INHB was superior to FSH in predicting the presence of haploid gamete (AUC: 0.73 vs 0.55, P < 0.05), with a sensitivity of 60.00% and a specificity of 80.28%. It concluded that serum INHB as an effective marker for spermatogenesis was a significant predictor of testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men. Especially, INHB is superior to FSH in predicting the presence of haploid gamete in the patients with elevated FSH.

INSL3 and AMH in patients with previously congenital or acquired undescended testes

BACKGROUND

In previous reports no differences in Leydig and Sertoli cell function were found between congenital undescended testis (CUDT) and acquired UDT (AUDT) on the basis of serum levels of LH, testosterone, FSH or inhibin B. This study tried to detect differences in Leydig and Sertoli cell function between CUDT and AUDT using insulin-like peptide 3 (INSL3) and anti-Müllerian hormone (AMH).

METHOD

118 men with a history of UDT (CUDT N=55 (6/55 bilateral), AUDT N=63 (15/63 bilateral)) were investigated. Differences between CUDT and AUDT, influence of age at surgery in CUDT, and effect of spontaneous descent or orchiopexy in AUDT were evaluated.

RESULTS

For INSL3, no significant differences were found. AMH levels in bilateral CUDT were significantly lower compared with bilateral AUDT (6.4 (1.7-11.4) vs 13.2 (6.1-30.1) μg/l, p=0.02). AMH levels in unilateral CUDT were significantly higher than in bilateral CUDT (12.1 (2.4-43.7) vs. 6.4 (1.7-11.4) μg/l, p=0.02).

CONCLUSION

No differences in Leydig cell function on the basis of INSL3 levels between the different UDT groups were found. Sertoli cell function evaluated by AMH, was more negatively affected in bilateral CUDT in comparison with bilateral AUDT and unilateral CUDT.

LEVEL OF EVIDENCE RATING

Level III Treatment Study.

Male factors in ART outcome prediction

Paternal influences on reproduction are significant causing about half of the infertile couples to turn to assisted reproductive techniques. Due to the increasing proportion of infertile couples adopting to conceive by in vitro fertilisation (IVF), predicting outcomes is of ever increasing importance. Since pregnancy rates following IVF are still quite low, prognostic information is very helpful in clinical decisions. Although significant research has been done on the maternal influence, male factor infertility is relatively understudied. To date, potential predictors include: method of fertilisation, age, reactive oxygen species, sperm quality parameters and DNA fragmentation. Predictors under investigation which show promising signs, even though there is no clear cut consensus on the predictive value to date include: folate and homocysteine, anti müllerian hormone measurement, environmental factors, body mass index, smoking, male age, stress, some subsets of antisperm antibodies and epigenetic features.

Inhibin at 90: from discovery to clinical application, a historical review

When it was initially discovered in 1923, inhibin was characterized as a hypophysiotropic hormone that acts on pituitary cells to regulate pituitary hormone secretion. Ninety years later, what we know about inhibin stretches far beyond its well-established capacity to inhibit activin signaling and suppress pituitary FSH production. Inhibin is one of the major reproductive hormones involved in the regulation of folliculogenesis and steroidogenesis. Although the physiological role of inhibin as an activin antagonist in other organ systems is not as well defined as it is in the pituitary-gonadal axis, inhibin also modulates biological processes in other organs through paracrine, autocrine, and/or endocrine mechanisms. Inhibin and components of its signaling pathway are expressed in many organs. Diagnostically, inhibin is used for prenatal screening of Down syndrome as part of the quadruple test and as a biochemical marker in the assessment of ovarian reserve. In this review, we provide a comprehensive summary of our current understanding of the biological role of inhibin, its relationship with activin, its signaling mechanisms, and its potential value as a diagnostic marker for reproductive function and pregnancy-associated conditions.

Age-dependent inhibin B concentration in relation to FSH and semen sample qualities: a study in 2448 men

Inhibin B is an important serum marker of spermatogenesis, whereas sensitivity and predicting power for the spermatogenic situation at several ages are under debate. We performed a retrospective analysis of data from 2448 men who attended our University-based male infertility clinic to evaluate inhibin B in relation to age and semen sample qualities in comparison with FSH. Moreover, the range of inhibin B in 82 nonobstructive azoospermic patients was correlated with the sperm retrieval in testicular sperm extraction procedures. Inhibin B correlated with FSH (Spearman rank correlation (R)=−0.50; P<0.00001). Inhibin B and inhibin B/FSH ratio (IFR) showed an inverse U-shaped dependence on age, whereas FSH showed a U-shaped dependence on age (optimum 20–40 years). However, in men with normal spermiograms inhibin B concentrations did not differ between age groups. Their levels of inhibin B amounted to 130.5, 54.5–247 ng/l (median, 10th–90th precentile), and of IFR to 38.3, 12.5–104.8 (median, 10th–90th percentile), which might be taken as the reference range. Using the 10th percentile of IFR, correct classification in normal or pathological semen groups was achieved in 99.1%. The percentage of aniline blue-negative spermatozoa, i.e. mature spermatozoa with protamines, did not correlate with FSH (P>0.05) but with inhibin B (R=0.15, P<0.001). The probability of retrieving testicular spermatozoa decreased with declining inhibin B: <20 ng/l sperm could never be found. Our results from a large group of men with a wide spectrum of semen qualities allow estimating reference values for inhibin B and IFR. Inhibin B and especially the IFR are more sensitive markers of male infertility than FSH alone.

Serum insulin-like factor 3 is highly correlated with intratesticular testosterone in normal men with acute, experimental gonadotropin deficiency stimulated with low-dose human chorionic gonadotropin: a randomized, controlled trial

OBJECTIVE

To study the potential role for using serum biomarkers, including insulin-like factor 3 (INSL3), 17α-hydroxyprogesterone, antimüllerian hormone, and inhibin B, as correlates of intratesticular T (IT-T) concentrations in men.

DESIGN

Prospective, randomized, controlled trial.

SETTING

University-based medical center.

PATIENT(S)

Thirty-seven healthy men aged 18-50 years.

INTERVENTION(S)

All men received the GnRH antagonist acyline, plus very low doses of hCG (0 IU, 15 IU, 60 IU, or 125 IU) SC every other day or 7.5 g T gel daily (75 mg delivered). The IT-T concentrations obtained by percutaneous testicular aspiration with simultaneous serum protein and steroid concentrations were measured at baseline and after 10 days of treatment.

MAIN OUTCOME MEASURE(S)

Intratesticular and serum hormone and gonadotropin concentrations.

RESULT(S)

After 10 days of gonadotropin suppression, serum INSL3 decreased by more than 90% and correlated highly with IT-T concentrations. In contrast, serum inhibin B, antimüllerian hormone, and 17α-hydroxyprogesterone did not correlate with IT-T. Serum INSL3 increased with the dose of hCG administered and returned to baseline after treatment.

CONCLUSION(S)

Serum INSL3 correlates highly with IT-T and serum T concentrations during acute gonadotropin suppression in men. Human chorionic gonadotropin stimulates dose-dependent increases in INSL3 and IT-T in healthy men and might be a useful biomarker of IT-T concentration in some clinical settings.

CLINICAL TRIAL REGISTRATION NUMBER

NCT# 00839319.

Testicular fine-needle aspiration versus testicular open biopsy: Comparable sperm retrieval rate in selected patients

BACKGROUND

Sperm recovery by testicular fine-needle aspiration (TESA) has resulted in variable sperm retrieval rate (SRR) and is generally considered inferior to open biopsy (testicular sperm extraction [TESE]).

AIMS

To develop a predictive model for SRR by TESA and to identify factors associated with comparable SRR between TESA and TESE.

SETTINGS AND DESIGN

Single-center controlled cross-sectional study on 450 infertile men with nonobstructive azoospermia.

MATERIALS AND METHODS

Clinical, paraclinical, and histological information of patients were gathered. All patients underwent both TESA and TESE in a single operation. Predictors of SRR by TESA were identified, and the accuracy of TESA in predicting the outcome of TESE was determined.

STATISTICAL ANALYSIS USED

Categorical and continuous variables were compared using independent t test and -chi-square test. Logistic regression model was applied to develop a predictive model for SRR by TESA. Receiver Operating Characteristics (ROC) curve analysis was used to determine the accuracy of TESA in predicting TESE outcome.

RESULTS

Sperm retrieval rate for TESA and TESE was 41.8 and 50.9%, respectively (P = 0.04). Age, duration of infertility, testis volume, luteinizing hormone, prolactin, and testosterone did not differ between patients with and without mature sperm in TESA samples. Serum follicular-stimulating hormone (FSH) < 15 IU/l (Exp (B) = 4.8, 95% CI: 1.4-18.5; P = 0.001) and histology of hypospermatogenesis (Exp (B) = 6.4, 95% CI: 2.1-27.4; P < 0.001) were predictors of SRR by TESA. In patients with FSH < 15 IU/l (57.4% versus 59.5%; Area under the curve (AUC) = 0.907) and testicular histology of hypospermatogenesis (68.0% versus 70.5%; AUC = 0.890), the SRR by TESA was predictive of SRR by TESE.

CONCLUSIONS

Serum FSH and testicular pathology were predictors of SRR by TESA. Patients with FSH < 15 IU/l and/or testicular pathology of hypospermatogenesis had comparable SRR by TESA versus TESE.

Gonadal function and parenthood 20 years after treatment for childhood lymphoma: a cross-sectional study

BACKGROUND

Gonadal function decades after treatment for childhood lymphoma (CL) is not well described. This cross-sectional study had two aims: (1) describe long-term gonadal function and fertility in childhood lymphoma survivors (CLSs), and (2) explore anti-Mullerian hormone (AMH) as a measure of ovarian function in CLSs.

PROCEDURE

Seventy-four male and 62 female CLSs participated in a survey consisting of a questionnaire, clinical examination, and blood/semen analysis. Prior treatment was categorized according to gonadotoxicity. Hypogonadism was determined by levels of gonadal hormones based on luteinizing hormone, follicle-stimulating hormone, testosterone (males), AMH (females <40 years), and menstrual status. Fertility was explored according to pregnancies achieved, semen analysis, and AMH.

RESULTS

Hypogonadism was observed in 7 of 66 males (11%). Seven of 64 males (11%) were categorized as infertile. Nine of 45 females <40 years (20%) were at risk to develop premature ovarian failure (POF). Twenty of 45 females (44%) showed low-AMH levels indicating decreased fertility. Four "critically low" females reported pregnancies within the preceding 2 years. Sixty-four percent of the males and 93% of the females attempting parenthood had been successful (P = 0.01). Hypogonadism and low-AMH were related to treatment burden.

CONCLUSION

Twenty years after treatment of CL, female CLSs' attempts of pregnancy initiation are mostly successful, while males seem at higher risk of infertility. Hypogonadism is a problem in 10% of the male CLSs. Based on AMH levels, POF is a risk in 20% of the female CLSs. The clinical significance of AMH reflecting true probability of fertility needs further research in cancer survivors.

Correlation between testicular sperm extraction outcomes and clinical, endocrine and testicular histology parameters in 120 azoospermic men with normal serum FSH levels

We retrospectively evaluated the clinical and hormonal profiles, sperm extraction outcomes and testicular histology parameters in 120 azoospermic men with normal serum follicle-stimulating hormone (FSH) level. Microsurgical epididymal sperm aspiration (MESA) and testicular sperm extraction (TESE) were performed in 33 and 87 cases, respectively. Sperm were successfully retrieved in all the MESA procedures and in 65 of the TESE procedures. The mean serum FSH and inhibin B levels and the testicular volume differed significantly according to whether or not sperm were retrieved. The threshold serum inhibin B value for predicting successful TESE was 123.5pg/mL (sensitivity: 69.7%; specificity: 66.7%). The 13 patients with Sertoli cell only syndrome (SCOS) had a higher mean serum FSH level and a lower mean serum inhibin B level than the other phenotypes. TESE was negative for 11 of the 13 SCOS men. The mean±SD inhibin B level was significantly lower in patients with 5-10IU/L of FSH than those with 2-5IU/L of FSH (108.30±53.86 vs. 175.23±70.17pg/mL, respectively). The sperm retrieval rates were 71.42% for the group with 5-10IU/L of FSH and 87.32% for the group with 2-5IU/L of FSH. Ten of the 13 SCOS men had a FSH level between 5 and 10IU/L. The clinical pregnancy rate was significantly lower (p=0.04) in the group with 5-10IU/L (50%) of FSH than in the group with 2-5IU/L (77.5%) of FSH. In conclusion, there is no FSH value below which spermatogenesis is always found. Inhibin B assays and clinical assessments are thus of particular value in men with normal serum FSH levels.

Assessment of male serum anti-Mullerian hormone as a marker of spermatogenesis and ICSI outcome

OBJECTIVE

To assess serum anti-Mullerian hormone (AMH) as a marker of spermatogenesis among fertile and infertile males, as well as its relation to ICSI outcome.

METHODS

A total of 77 male partners of infertile couples seeking infertility treatment were recruited for this study. They were classified according to the WHO criteria of semen analysis into three groups; azospermia, oligospermia, and normal. All participating patients had a serum assay of the level of AMH. Thirty-three couples out of the previously mentioned 77 couples underwent controlled ovarian stimulation and ICSI.

RESULTS

There were 41 patients with azospermia, 14 patients with oligospermia, and 22 patients with normal count. There was no significant difference among the three groups regarding the AMH levels. There was no significant correlation between the AMH levels from all patients and the sperm concentration (rho = 0.03, p = 0.82). Among patients who underwent ICSI, there was no significant correlation of the AMH with the age, sperm concentration, fertilisation percent or number of embryos. The age of male partners was significantly correlated with sperm concentration, fertilisation percent and the total number of embryos. In the logistic regression model used, serum AMH had no significant relation to clinical pregnancy.

CONCLUSION

Male serum AMH levels are not indicative of spermatogenesis and cannot differentiate between fertile and infertile males. Serum AMH levels were not predictive of ICSI outcome as well.

Decrease of anti-Mullerian hormone in genetic spermatogenic failure

The aim of this study was to compare anti-Mullerian hormone (AMH) plasma levels in patients with azoospermia according to the physiopathology. In a prospective clinical study from April 2008 to March 2009 in University Hospital, we measured AMH levels in 49 consecutive patients with azoospermia. AMH plasma levels were correlated with FSH, inhibin B, bioavailable testosterone plasma levels and testicular volume and compared between nonobstructive azoospermia (NOA) and obstructive azoospermia (OA) and within four physiopathological subgroups of NOA: genetic, cryptorchidism, cytotoxic and unexplained. AMH, FSH, inhibin B, bioavailable testosterone plasma levels and testicular volumes were all related to each other. AMH plasma levels were lower in NOA relatively to OA. Lowest values were observed in cases of genetic NOA and on the other hand, the values observed in case of cytotoxic NOA were as high as the values observed in OA. FSH, inhibin B, bioavailable testosterone and testicular volume were not different between genetic and cytotoxic NOA. These results suggest that the decrease in AMH plasma levels is related to the origin of NOA, with low values in genetic NOA and values similar to OA in cytotoxic NOA. Further studies will be useful to understand the fine regulation of AMH production.

Evaluation of Serum Testosterone, Progesterone, Seminal Antisperm Antibody, and Fructose Levels among Jordanian Males with a History of Infertility

Due to the biochemical complexity of seminal fluid, we attempt to study the possible correlation between fructose, which is secreted under the effect of androgen hormone, and autoimmunity, which might play a role in varicocele associated infertility, in reducing sperm motility. Seminal fructose, antisperm antibodies (ASAs) and blood steroids hormones (testosterone and progesterone) levels were measured in 66 infertile males with varicocele and 84 without varicocele referred for fertility treatment. Seminal analysis was performed with biochemical measurements of seminal fructose and mixed agglutination reaction (MAR) for ASA. Serum levels of progesterone and testosterone were estimated using a competitive chemoluminescent enzyme immunoassay. The mean values for serum testosterone were 380.74 ± 24.331, 365.9 ± 16.55, and 367.5 ± 21.8 ng/dl, progesterone 0.325 ± 0.243, 0.341 ± 0.022, and 0.357 ± 0.0306 ng/ml, and seminal plasma fructose 359.6 ± 26.75, 315.6 ± 13.08, and 332.08 ± 24.38 mg/dl in males with varicocele, without varicocele, and fertile males, respectively. A significant high level of testosterone was observed within varicocele group (P = .001). This result showed that testosterone may play a role as an infertility determinant in subjects with varicocele. ASA was detected in 18 (26.47%) of cases with varicocele, 20 (38.46%) without varicocele, and in 16 (32.0%) fertile men. Cases with ASAs associated with low sperm motility morphology. An inverse correlation between sperm-bound antibodies and viscosity has been shown (P = .017). ASA showed some significant inverse relations with ages, durations of infertility, and viscosity (P < .05). In addition, a significant correlation was observed between ASA positive seminal plasma and testosterone concentration among infertile cases (with or without varicocele) and fertile (P < .05). Our results suggest a relationship between testicular steroid hormone levels with autoimmunity and sperm antibodies which influence the motility of ejaculated spermatozoa among Jordanian infertile males.

Association between neuropeptide oxytocin and male infertility

PURPOSE

To investigate the relationship between oxytocin (OT) and male infertility, serum OT baseline concentration and oxytocin receptor (OTR) gene expression in fertile and infertile men were investigated.

METHODS AND PATIENTS

Twenty obstructive azoospermia patients, twenty five idiopathic asthenozoospermia patients, twenty idiopathic oligozoospermia patients and twenty healthy subjects were taken into consideration. Serum OT baseline concentration was determined by radioimmunoassay. Moreover, serum concentration of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (T) were determined by chemoluminescence to evaluate the correlation with OT. OTR gene promotor and OTR mRNA expressions were determined by polymerase chain reaction and reverse transcriptase-polymerase chain reaction, respectively. OTR protein expression was also performed by Western Blot.

RESULTS

Serum OT baseline concentrations in infertile groups were significantly higher than in fertile group (F0.05/2(2,82) = 8.29, p < 0.001). Serum baseline concentration of OT was not correlated with that of LH, FSH and T. There was no significant difference in gene sequences of OTR gene promotor and OTR mRNA when comparing infertile patients with fertile. Human OTR was in the form of oligomers and monomers, and the oligomers were in the majority containing tetramers and hexamers. Monomer expression was significantly higher in idiopathic asthenozoospermia and idiopathic oligozoospermia than that in obstructive azoospermia and control group (F0.05/2(2,82) = 115.50, p < 0.001). There was no significant difference in oligomer expression between different groups, but 20% of idiopathic asthenozoospermia cases showed a decrease.

CONCLUSIONS

Significantly different OT baseline concentrations and OTR expressions between fertile and infertile men strongly suggest that OT/OTR system is likely to be linked with male infertility, providing new insights into the pathogenesis and treatment of male infertility.